I know that the Shimano Nexus internally-geared hubs are intended to be used with horizontal dropouts, as the axles have flats which prevent them rotating in the dropouts under pedalling load.

Does anyone know if Sturmey-Archer or SRAM internally geared hubs can be used with vertical dropouts? I'm currently thinking about the design of a custom-built frame (edit: with eccentric bottom bracket for adjusting chain tension), and I'd like to be able to use it with disc brakes (hence prefering vertical dropouts) but preserving the possibility of using internal gears if I can.

I suspect your biggest concern with vertical dropouts will be getting the right chain tension. You may have to use a half link as sold by Harris Cyclery to get the chain length correct.

I should have stated right off - I'm planning on an eccentric bottom brake for chain tension adjustment. I primarily intend to ride the bike either fixed or single-speed, with disc brakes. I just like internally geared hubs, and I want to make sure I keep open the option of using them.

I hope somebody can answer the question. I've got a "magic gear" single speed Trek 930 mtb that I'd like to put a Sturmey-Archer hub on.

Well, actually, I think I've answered my own question, at least with regards to SRAM hubs. I found they have full technical manuals on their site, and their internal hubs do require horizontal dropouts. They have an "anti-rotation" insert for the dropouts. I've decided that the best option for my bike is probably short horizontal dropouts - not using any of the (limited) horizontal range for adjustment, but having it available for internally geared hubs.

Did you know that you can still buy new Sturmey-Archer hubs from permaco.com?

Yes, I did! S-A stuff is still in production in Taiwan, and they're even introducing many new models. They have an 8-speed hub with a disc brake mount, but its gearing is really weird.

Generally speaking, you need horizontal dropouts for internal-geared hubs, to prevent the axle from rotating. It's not a matter of chain tension. There are some very few hubs (like one of the several versions of the Rohloff) that can be used with vert drops, though I only know of the Speedhub. The other option open to you is to work something out with some inventiveness, spare parts and maybe a power drill that will hold things securely in place. Good luck, if you decide to go that route. It's been done, but it will require some ingenuity.

Vertical dropouts - great for derailer bikes, enormous pain in the fanny for anything else .

Im pretty sure that those devices don't do anything. At least I'm not using them on my shimano. Toss them I say. The axle doesn't rotate. Why would it?

Those "no turn" washers are vital. I strongly suggest you dig them out of the trash bin and put them back on.
The planetary gearing levers against the sun gear which is fixed to the axle shaft. The forces which propel the wheel forward are also trying to turn the axle backward. The power flow simply follows the path of least resistance. If the axle is not braced against rotation by means of the "no turn" washers at the least, or ideally by means of a torque arm, you may be powering up a hill one day when the torque suddenly finds it easier to turn the axle backward than to turn the wheel forward. This will cause your bearings to become mal-adjusted, and will be the beginning of many problems with your hub.

Those "no turn" washers are vital. I strongly suggest you dig them out of the trash bin and put them back on.
The planetary gearing levers against the sun gear which is fixed to the axle shaft. The forces which propel the wheel forward are also trying to turn the axle backward. The power flow simply follows the path of least resistance. If the axle is not braced against rotation by means of the "no turn" washers at the least, or ideally by means of a torque arm, you may be powering up a hill one day when the torque suddenly finds it easier to turn the axle backward than to turn the wheel forward. This will cause your bearings to become mal-adjusted, and will be the beginning of many problems with your hub.

Dan Burkhart

Hey thanks for the info. The hub has a couple of cone locknuts on top of the first one and it hasn't slipped yet but I think I better go find those pieces.